Air conditioning system



Oct. 4, 1966 R. E. JAPHET 3,276,516

AIR CONDITIONING SYSTEM Filed April 26, 1965 2 Sheets-Sheet 1 I "I I "I /3G 65 L.

I42 40 g1 46 31 I A 7| FIG. I RICHARD EJAPHET INVENTOR.

BM M M United States Patent 3,276,516 AIR CONDITIONING SYSTEM Richard E. Japhet, Livingston, N.J., assignor to Worthington Corporation, Harrison, N.J., a corporation of Dela- In general, this invention relates to a new and improved air conditioning system and, more particularly, apparatus which is operative to efliciently utilize the components of a building air conditioning system during both form and cool weather conditions.

In the past, a well-known system for operating a building air conditioning apparatus utilized a split condenser operative with two separate water loops, one of which included a cooling tower mounted outside of the building. The cooling tower creates many problems. For example, dirt and other residues can be drawn into the cooling system and require periodic condenser tube cleaning which, accordingly, causes the maintenance cost of the system to rise. Further, even during the light loads such as are present during the cool weather seasons, it is still necessary to air condition the building, and all of the air conditioning equipment must be operative. This includes the necessity of operating the compressor which forms a portion of a split condenser, and the pump in the hot water loop of the system. These units require considerable power to operate, and accordingly, the cost of running the system remains high.

However, in the above-mentioned prior .art system, there was no utilization of the ambient temperature outside the building to susbtantially reduce the cost of operating the cooling system. Thus, it has been recognized that due to the modern construction methods and high intensity lighting, maximum occupancy of a large multistory building creates a large amount of internal heat which is to be removed to achieve com-fort conditions. This is true even on relatively cool days when the perimeter of the building already requires heat. The prior art system utilizes the internal cooling load as condenser heat and transfers it to the perimeter of the building. However, this system has disadvantages which only partially compensate for the advantages inherent in being able to transfer the internal heat of the building to the perimeter thereof. These disadvantages include: (a) the need for the cooling water tower, (b) the need for two pumps to operate even when there are cool ambient conditions, and (c) the need for operation of the refrigerator loop under cool ambient conditions.

Thus, it is the general object of this invention to avoid and overcome the foregoing and other difficulties of prior art practices by the provision of a new and better apparatus for operating a building air conditioning system which eliminates the requirement of a dual c'ircuited condenser during cool weather use as has been necessary in prior art system.

Another object of this invention is the provision of a new and better apparatus for a building air conditioning system which avoids condenser contamination.

Still another object of this invention is the provision of a new and better apparatus for a building air conditioning system which eliminates the need for a cooling tower 3,276,516 Patented Oct. 4, 1966 pump and cooling tower and, further, eliminates the need for two condenser cooling circuits during cool weather use.

A further object of this invention is the provision of a new and better apparatus for a building air conditioning system which is capable of removing interior heat with simultaneous reheating or perimeter heating.

A still further object of this invention is the provision of a new and better apparatus for a building air conditioning system which is operative during the cooler seasons to be utilized without the compressor.

Still another object of this invention is the provision of a new and better apparatus for a building air conditioning system which can be utilized with the boiler during the hot weather to aid in the heating when the additional heat produced by the refrigeration loop is insufiicient.

Other objects will appear hereinafter.

For the purpose of illustrating the invention, there is shown in the drawings a form which is presently preferred; it being understood, however, that this invention is not limited to the precise arrangements and instr-umentalities sh own.

FIGURE 1 is a schematic showing of the apparatus for a building air conditioning system built in accordance with the principles of the present invention with the arrows thereon showing the direction of the water while the system is operating in warm weather conditions.

FIGURE 2 is a schematic similar .to FIGURE 1 show ing the air conditioning system in operation under cool weather conditions.

In FIGURE 1 is there is shown, schematically, the building air conditioning system generally designated by the numeral .10. The system 10 includes, a compressor 12, a condenser 14, and chiller 16 which are part of a standard condenser apparatus 18. Additionally, there is provided an evaporative cooler 20 of standard construction which is mounted on the outside of the building.

The refrigeration loop means 18 is well 'known in prior art systems. That is, the compressor 12 compresses refrigerant from chiller outlet line 22 and feeds the compressed refrigerant through condenser inlet line 24 to the condenser 14. The-re, refrigerant gives up heat to water from the evaporative cooler 20 passing through the condenser 14. The now condensed refrigerant passes through an expansion valve means, an expansion device 26 in the outlet of the condenser, and expands as it is fed into the chiller or evaporator 16. Within the chiller 16, the refrigerant removes heat from water within the cooling circuit to be described below. After absorbing the heat from said water, refrigerant passes out the chiller outlet conduit 22 to complete the cycle. A suitable bypass line 28 is provided with a valve 30 for bypassing the compressor 12. As was stated previously, the condenser 14 is of a standard type and does not, per se, form a portion of the present invention. The cold water circuit or cooling loop operative with the chiller 16 includes a cold water pump '32 supplied from the outlet line 34 of the chiller 16 through an inlet conduit 36 for the cold water pump. The inlet conduit 36 is also connected to one port 58 of a three-way valve or switching means 38 which port 58 is closed during summer operation as has been shown in 'FIGURE 1. The operation of three-way valve 38 will be described below. The cold pump 32 feeds various room air conditioning units 40 within the building. After passing through the room air conditioning units 40, the cold u water is fed through two ports 42 and 44, normally opened, of three-way valve or switching means 46. Port 44 is connected to the inlet line 48 of the chiller 16 thus completing the air conditioning circuit. The three-way valve 46 also has a third port 50 which is closed during the summer operation.

The second water circuit or hot loop means for cooling the refrigerant passing through condenser 14 includes an inlet line 52 supplying hot water to the evaporative cooler 20. Within the evaporative cooler or heat exchange in communication with a sink, the water is cooled and directed through outlet conduit 54 to one port '56 of the three-way valve 38. The three-way valve 3 8 has three ports 56, 58, and 60. Port 58 is connected to the inlet conduit 36 of the cold water pump 32. However, the three-way valve 38 maintains, for the operation shown in FIGURE 1, the port 58 closed. The port 60 is opened .and thus water from the evaporative cooler outlet conduit "54 passes into the condenser 14 through ports 56 and 60. After passing through the condenser and absorbing heat from the refrigerant in the condenser, the now hot -water passes through a condenser outlet conduit 62 to a boiler 65 and thence to hot water pump 64.

From the hot water load 66 the said conduit 68 to the normally opened ports 67, 69 of three-way valve 71, past the normally closed port 50.

From the hot Water load 66 the hot water is directed through an outlet conduit 68, past the normally closed port 50 of three-way valve 46, to the inlet conduit 52 of the evaporative cooler 20. A bypass valve 70 is connected across the inlet and outlet lines 52 and '54 of the evaporative cooler 20. Should the temperature in the outlet conduit 54 drop below a preset value as determined by a heat sensitive member 72, the valve 70 will open and bypass some of the hot water into the outlet conduit 54 Three-way valve 71 has a third port 73 connected to the boiler 65. Should the hot water load 66 drop below a predetermined temperature, a temperature sensor 75 will transmit a signal in accordance with the temperature of the Water in the hot water load 66 to control the opening of port 73 and, thus, to bypass a portion of the water flowing through conduit 68. This additional water in boiler 65 will increase the temperature in the hot water load.

In many senses, it would appear that the system shown in FIGURE 1 is substantially similar to the prior art system discussed previously with the substitution of the evaporative cooler for the cooling tower, and eliminating the need for a split condenser. Of course, by utilizing the evaporative cooler it is possible to maintain the apparatus 10 in closed water loops so as to avoid contamination of condenser tubes and, thus, maintenance costs are substantially reduced. However, in addition, by utilizing the three-way valves 2-8 and 46 in the manner to be discussed with respect to FIGURE 2, it is possible to obtain even more substantial savings during the operation of the apparatus 10 in cool or cold Weather conditions.

That is, in FIGURE 2, there is shown the manner in which the three-way valves 38 and 46 are operative to eliminate the need for the condenser '14 and the hot water pump 64 during cold weather operation of the system. That is, in FIGURE 2, the three-way valve 38 has been operated in a manner whereby ports 56 and 58 are opened and port 60 is closed. Further, three-way valve 46 is operative in a manner whereby ports 42 and 50 are opened and port 4 4 is closed. Thus, by this simple changeover of the three-way valves 68 and 46, the split condenser 18 can be completely bypassed, as weh as the hot water system including the hot water pump 64. This can be called a free-cooling system because of its use of the ambient rather than a compressor to remove heat from the system. Then, only a single water circuit is present, which water circuit will operate as follows:

Water passes through the inlet conduit 52 int-o the evaporative cooler 20. Since the evaporative cooler 20 is on the outside of the building, it is possible to cool the water 52 to a temperature approaching the ambient. Then, this cold water will pass out conduit 54 and through open ports 56 and 58 of three-way valve 38. From port 58, the cold water Will be pumped by pump 3-2 into the air conditioning units 40. From the air conditioning units 40, the water will pass through the open ports 42 and 50 into the inlet conduit 52 thus completing the cooling circuit. Bypass valve 70 and its associated sensor 72 can still be utilized in accordance with the teachings of the present invention.

If desired, the portion of the hot water system including the hot water load 66, pump 64 and boiler 65, and three-way valve 71 can still operate during the free-cooling cycle by merely closing port 69 and allowing water to flow only in the closed loop formed by the above combination. This closed loop can still, of course, be regulated by the temperature sensor 75.

It can be seen that the cost of running the compressor 12 has been eliminated by bypassing the condenser 14. Further, by not utilizing a cooling tower the system can be maintained with a minimum of maintenance costs as contamination elements are not allowed into the system. Further, the advantages of the two-circuit system with its ability to achieve perimeter heating and full utilization of the ambient have been maintained for warm weather use.

The auxiliary boiler can be incorporated into the hot water loop and operated independently if desired. As was stated above, where only minor heating is needed in a building and, substantial cooling is desired, under cold ambient conditions which is typical for occupancy hours of large oflice buildings, the free-cooling loop can be used with the boiler being operative to supply whatever heating is necessary for the building.

In view of the foregoing, the objects of this invention have been achieved by the simple utilization of an evaporative cooler for the cooling water found in prior art systems and, further, the ntilization of the three-way valves 38, 46 and 71. Further, control of the amount of cooling can be achieved by proper regulation of the bypass valves 70 and 30.

The present invention may be embodied in other specific forms without departing from the spirit or essential attributes thereof and, accordingly, reference should be made to the appended claims rather than to the foregoing specification as indicating the scope of the invention.

I claim as my invention:

1. An air conditioning system for an enclosure comprising:

(a) a refrigeration loop having a compressor, a condenser, and an evaporator operatively connected to each other to form said loop,

(b) a plurality of cooling terminal units for passing cool liquid therethrough,

(c) a first pump,

(d) a first conduit means normally connecting the first pump, the plurality of terminal units, and the evaporator of the refrigeration loop to form a cooling loop whereby liquid will normally be circulated from the evaporator of the refrigeration loop to the plurality of cooling terminals and back again,

(e) a plurality of heating terminal units for hot liquid therethrough,

(f) a second pump,

(g) an evaporative cooler,

(h) a second conduit means normally operatively connecting the evaporative cooler, the second pump, the plurality of heating terminal units, and the condenser of the refrigeration 'loop to form a hot loop whereby liquid Will normally be circulated from the' evapora tive cooler to the condenser of the refrigeration loop and then through the heating terminal units," and back again, I

passing (i) a first valve means disposed in the cooling loop to normally permit operation of the cooling loop,

(j) a first interconnecting conduit means connected between the first valve means and the hot loop means upstream of the evaporative cooler,

(k) a second valve means disposed in the hot loop to normally permit operation of the hot loop,

(1) a second' interconnecting conduit means connected between the second valve means and the cooling loop upstream of the plurality of cooling terminal units,

(In) the first and second valve means being operative to prevent operation of the normal cooling and hot loops and causing the bypassing of the condenser and the evaporator of the refrigeration loop and permitting the liquid to be continuously circulated by one of the pumps from the evaporative cooler to the plurality of cooling terminal units and back again to form a closed cooling bypass loop.

2. The combination of claim 1 including:

(a) a bypass line connected between the upstream side and the downstream side of the evaporative cooler,

(b) a regulator valve disposed in the bypass line to control the flow of liquid therethrough.

3. The combination of claim 2 including:

(a) temperature control means connected to the regulator valve,

(b) the temperature control means signaling the temperature downstream of the bypass line connection, and

(c) said regulator valve controlling the fiow of liquid through the bypass line in response to said temperature control means signal.

4. An air conditioning system for selectively conditioning an enclosure comprising:

(a) a first heat exchanger in combination with heat sink,

(b) a second heat exchanger,

(c) a third heat exchanger,

(d) at least one, fourth heat exchanger,

(e) at least one, fifth heat exchanger,

(f) a compressor disposed between the inlet and outlet of said second and third heat exchangers,

(g) an expansion device disposed between the outlet and inlet conduits of said second and third heat exchangers,

(h) a first conduit means connecting the compressor, the second heat exchanger, the expansion device, and the third heat exchanger into a continuous circuit to form a closed refrigeration loop,

(i) a second conduit means connecting the first heat exchanger, the second heat exchanger, and the fifth heat exchanger into an operative heating loop,

(j) a third conduit means connecting the third heat exchanger and the fourth heat exchanger into an operative cooling loop,

(k) a first pu mp disposed in one of the heating or cooling loops to force the circulation of liquid therein,

(1) a second pump disposed in the other cooling or heating loop to force the circulation of liquid therein,

(-m) a fourth conduit means interconnecting a portion of the heating loop and the cooling loop to form a cooling bypass loop including the first heat exchanger, the fourth heat exchanger, and at least one of said pumps, and

(n) a pair of three way valves, one disposed in the heating loop, and one disposed in the cooling loop, said valves nonmally permitting operation of said loops, and further, being operative to connect said first and fourth heat exchangers to said fourth conduit means to form said bypass cooling loop to bypass the refrigeration loop and the heating loop whereby liquid will be continuously circulated in the bypass cooling loop whereby the other of said loops may be shutdown.

G 5. The combination of claim 4 wherein: (a) the three-way valve in the heating loop is disposed downstream of the first heat exchanger, (b) the three-way valve in the cooling loop is disposed.

downstream of the fourth heat exchanger, and

(c) one of the pumps is disposed on the upstream side of the fourth heat exchanger to provide a forced circulation of the liquid in the bypass cooling loop. 6. The combination of claim 5 wherein the other of the pumps disposed in the heating loop is upstream of the fifth heat exchanger.

7. The combination of claim 6 wherein:

(a) the fourth heat exchanger includes a plurality of terminal units, and

(b) the fifth heat exchanger includes a plurality of terminal units.

8. An air conditioning system for an enclosed area comprising (a) a refrigeration loop means having a compressor, a condensor and an evaporator operatively connected to each other in closed arrangement,

(b) a cooling loop means interconnected with the evaporator of the refrigeration loop means to cool the liquid in the cooling loop during normal operation of the refrigeration loop means,

(0) a plurality of terminal units disposed in the cooling loop means within the enclosed area,

(d) a pump means disposed in the cooling loop means to supply motive power to the liquid circulated therein,

(e) a hot loop means interconnected with the condenser of the refrigeration means to heat the liquid in the hot loop means,

(f) a plurality of terminal units disposed in the hot loop means,

(g) a pump means disposed in the hot loop means to supply motive power to the liquid circulated therein,

(h) a heat exchanger in communication with a sink,

normally disposed in the hot loop means,

(i) loop switching means disposed in said hot loop means downstream of the heat exchanger and said cooling loop means downstream of the cool terminal units, the loop switching means normally positioned to permit uninterrupted operation of the hot loop means and the cooling loop means and adapted to be positioned in a bypass arrangement,

(j) conduit means extending from the loop switching means to interconnect the hot loop means and the cooling loop means to term a bypass cooling loop means including the heat exchanger and the cool terminal units whereby on operation of the loop switching means from the normal position to the bypass position the liquid will be continuously circulated in the bypass cooling loop means, and

(k) a motive means disposed in the bypass cooling loop means, adopted to be one of said pump means, to force feed the liquid circulated therein.

9. The combination claimed in claim 8 wherein:

(a) the heat exchanger including an evaporative cooler in communication with the sink,

10. The combination claimed in claim 9 wherein:

(a) the pump means idefining the motive means of the bypass cooling loop means disposed downstream of the evaporative cooler and upstream of the cooler terminal units.

11. The combination claimed in claim 8 wherein:

(a) a secondary heat source disposed in the hot loop means downstream of the condenser and upstream of the hot terminal units to be selective-1y operated to supplement the heat supplied from the refrigeration loop means,

(b) a three-way valve disposed on the downstream of the hot terminal units, and

(c) a conduit means interconnected between the threeway valve and the secondary heat source to recycle a portion of the liquid in the hot'loop means through 1 the secondary heat source to the hot terminal units I may be operative simultaneously with and independently of the bypass cooling loop means. 13. The combination claimed in claim 12 wherein: (a) the pump means in the hot loop means disposed j between the secondary heat source and the hot terminal units.

References Cited by the Examiner UNITED STATES PATENTS Durbin 62-324 Crawford 62157 McFarlin 62-459 Harnish 62435 Blum 62435 Ringquist 62185 Ringquist 62--159 Ringquist 62-159 WILLIAM J. WYE, Primary Examiner. 

8. AN AIR CONDITIONING SYSTEM FOR AN ENCLOSED AREA COMPRISING: (A) A REFRIGERATION LOOP MEANS HAVING A COMPRESSOR, A CONDENSOR AND AN EVAPORATOR OPERATIVELY CONNECTED TO EACH OTHER IN CLOSED ARRANGEMENT, (B) A COOLING LOOP MEANS INTERCONNECTED WITH THE EVAPORATOR OF THE REFRIGERATION LOOP MEANS TO COOL THE LIQUID IN THE COOLING LOOP DURING NORMAL OPERATION OF THE REFRIGERATION LOOP MEANS, (C) A PLURALITY OF TERMINAL UNITS DISPOSED IN THE COOLING LOOP MEANS WITHIN THE ENCLOSED AREA, (D) A PUMP MEANS DISPOSED IN THE COOLING LOOP MEANS TO SUPPLY MOTIVE POWER TO THE LIQUID CIRCULATED THEREIN, (E) A HOT LOOP MEANS INTERCONNECTED WITH THE CONDENSER OF THE REFRIGERATION MEANS TO HEAT THE LIQUID IN THE HOT LOOP MEANS, (F) A PLURALITY OF TERMINAL UNITS DISPOSED IN THE HOT LOOP MEANS, (G) A PUMP MEANS DISPOSED IN THE HOT LOOP MEANS TO SUPPLY MOTIVE POWER TO THE LIQUID CIRCULATED THEREIN, (H) A HEAT EXCHANGER IN COMMUNICATION WITH A SINK, NORMALLY DISPOSED IN THE HOT LOOP MEANS, (I) LOOP SWITCHING MEANS DISPOSED IN SAID HOT LOOP MEANS DOWNSTREAM OF THE HEAT EXCHANGER AND SAID COOLING LOOP MEANS DOWNSTREAM OF THE COOL TERMINAL UNITS, THE LOOP SWITCHING MEANS NORMALLY POSITIONED TO PERMIT UNINTERRUPTED OPERATION OF THE HOT LOOP MEANS AND THE COOLING LOOP MEANS AND ADAPTED TO BE POSITIONED IN A BYPASS ARRANGEMENT, (J) CONDUIT MEANS EXTENDING FROM THE LOOP SWITCHING MEANS TO INTERCONNECT THE HOT LOOP MEANS AND THE COOLING LOOP MEANS TO FORM A BYPASS COOLING LOOP MEANS INCLUDING THE HEAT EXCHANGER AND THE COOL TERMINAL UNITS WHEREBY ON OPERATION OF THE LOOP SWITCHING MEANS FROM THE NORMAL POSITION TO THE BYPASS POSITION THE LIQUID WILL BE CONTINUOUSLY CIRCULATED IN THE BYPASS COOLING LOOP MEANS, AND (K) A MOTIVE MEANS DISPOSED IN THE BYPASS COOLING LOOP MEANS, ADOPTED TO BE ONE OF SAID PUMP MEANS, TO FORCE FEED THE LIQUID CIRCULATED THEREIN. 